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Omega-3 Fatty Acids May Prevent Cellular Aging

Your cells are constantly dying and being replaced by new cells, which
are created by cell division. Telomeres are DNA sequences, and multiples
of these telomeres form a protective cap on the ends of certain
chromosomes. As these chromosomes are divided to create new cells,
one or more of these telomeres are stripped from the ends of the
chromosomes, which eventually leads to the breakdown of the chromosome
and cellular death.

While it is natural and normal for cells to die,
which is known as "programmed cell death," emerging research posits
that the number of telomeres present on certain cells is linked to
biological aging, which is different from chronological age in that
these telomeres are also affected by genetic and environmental factors.
These negative factors can accelerate cellular death, and premature
cellular death is linked to inflammatory states such as high blood
pressure, heart disease and cancer.

We know that omega-3 fatty acids are instrumental in preventing heart
disease, which is at is most basic level is an inflammatory state
in the body, but we don't exactly know why. Researchers at UC San
Francisco, along with researchers at San Francisco Veterans Affairs
Medical Center and Sanford School of Medicine in South Dakota, recently
teamed up to perform an interesting study on the length of those
telomeres and omega-3 fatty acids (JAMA 2010;303(3):250-257).

The researchers began by recruiting 608 men who had previously had a
heart attack but were considered stable. At the start of the study
the researchers gathered the standard demographic information on
each participant, including height, weight, age, physical activity,
education, etc.. They also drew blood and tested their cholesterol
levels as well as measuring the amount of fish- or shellfish-sourced
omega-3 fatty acids in their blood.

Further, the researchers isolated certain types of DNA from the participants
and were able to count the number of telomeres (on average) attached
to the DNA of each participant. Five years later, they performed
the same DNA tests, measuring how much those telomeres had shortened,
and compared the results for each subject with their results from five
years before and the amount of omega-3 fatty acids in their blood.

For purposes of comparison, the researchers grouped the participants
into five increasing levels of bloodstream omega-3s. Compared to
those with the lowest amount of bloodstream omega-3s, those with
the highest amount of omega-3s saw the least shortening of telomeres
in their DNA.

What this means for you

This is pretty complex stuff but it helps point toward just why omega-3s
are good for you. The authors of this study note that to really know
for sure whether omega-3s are one of the factors responsible for
maintaining those telomeres is to perform a long-term, placebo-controlled
study. For you, just keep eating and enjoying your fish, knowing
that it's delicious and great for you.